1. Field of the Invention
The present invention relates generally to a web splicing apparatus for splicing web materials, and more particularly to a splicing apparatus for splicing long flexible sheet materials such as plastic film, paper and foil (hereinafter referred to as a web) by splicing two ends of the webs of an old roll and a new roll while continuously supplying the web.
2. Description of the Related Art
U.S. Pat. No. 3,654,035 which corresponds to Japanese Patent Publication No. 48-38461 has disclosed an example of a conventional web splicing apparatus. This web splicing apparatus consists of a web turret, a web cutting and splicing means, and so forth.
The turret has a turret arm, and an old roll and a new roll are pivotally supported by two ends of the turret arm. The web is continuously supplied to the cutting and splicing means by changing the positions of the old roll and the new roll. The cutting and splicing means has a cutting drum and a splicing drum. The cutting drum cuts the trailing end of the web of the old roll, which is being unwound, and the leading end of the web of the new roll where the unwinding starts while continuously supplying the web. The splicing drum splices the web ends with splicing tape while continuously supplying the web.
The splicing tape must be supplied to the splicing drum in advance. Some of the conventional splicing tape supply devices have been disclosed in U.S. Pat. No. 4,636,276 which corresponds to Japanese Patent Publication No. 63-3819, Japanese Patent Provisional Publication No. 61-90954. The conventional splicing tape supply device supplies the splicing tape in a direction perpendicular to the longitudinal direction of the webs, and has a base assembly for supplying the splicing tape, a shifting mechanism for moving the base assembly in a direction perpendicular to the longitudinal direction of the webs.
As shown in FIG. 12, when a cutter 3 cuts a trailing end 1A of a web 1 of an old roll and a leading end 2A of a web 2 of a new roll while continuously supplying the webs 1 and 2, the ends 1A and 2A are cut at a predetermined angle of inclination .theta..degree. with respect to the longitudinal direction of the webs 1 and 2. The web ends 1A and 2A are spliced together by the above-mentioned splicing tape supply device. Since the supply device supplies the splicing tape 4 in a direction perpendicular to the longitudinal direction of the webs, the splicing tape 4 wrinkles as shown in FIG. 13, and the web ends 1A and 2A cannot be spliced together satisfactorily.